ANATOMY

Detailed explanation-1: -Abstract. The ureteric bud (UB) is an epithelial tube that arises from the nephric duct and branches repetitively to give rise to the renal collecting duct system while also generating inductive signals that promote nephrogenesis by surrounding metanephric mesenchyme (MM) cells.

Detailed explanation-2: -There are two embryonic kidney precursors, the pronephros and mesonephros. Remarkably, these precursors take form and then involute and yet are necessary for development of the definitive kidney, as interruption of their development results in renal agenesis.

Detailed explanation-3: -By week 5, the ureteric bud undergoes a sequence of bifurcations and branching to eventually form the renal pelvis, the major and minor calyces, and the collecting ducts.

Detailed explanation-4: -Thus, the two intermediate mesodermal tissues-the ureteric bud and the metanephrogenic mesenchyme-interact and reciprocally induce each other to form the kidney (Figure 14.19). The metanephrogenic mesenchyme causes the ureteric bud to elongate and branch.